upgrading brompton b75

[berlinonaut]

Berlinonaut, I have it on good authority that any 3-lug sprocket will work on the Sachs 6-speed. The cutaway teeth aren't vital and only serve to speed up shifting slightly. Or you could modify a sprocket with a grinder or file, if you want to. It's not Hyperglide-level tooth shaping.

Yup, that's my personal opinion as well. Still many Brompton dealers and workshops do either not know that or ignore that. As a consequence a not technically interested or competent Brompton rider get's told by the Brompton dealer: "Part no longer avail." I personally know strories of people that for that reason have upgraded to a new rear wheel (BWR or BSR). I find it understandable that not all dealers are willing to experiment or take the risk but rely on factory supply.

 

[berlinonaut]

Which means can be easily reproduced with equal or close to equal quality by Chinese manufacturers. And based on what we've seen in smartphone market, they can take over the market pretty quick as they know what they are doing.

While there is some truth to that it is by far not that simple. This topic has been excessively discussed in other threads on that forum, so no sense for me to replicate this discussion. In the end, with all constraints, it is capitalism: If Brompton f*** it up they f*** it up. They have to play their cards and while not everything lies in their own hands there is a lot what they can do right or wrong.

 

[rogerzilla]

Yup, that's my personal opinion as well. Still many Brompton dealers and workshops do either not know that or ignore that. As a consequence a not technically interested or competent Brompton rider get's told by the Brompton dealer: "Part no longer avail." I personally know strories of people that for that reason have upgraded to a new rear wheel (BWR or BSR). I find it understandable that not all dealers are willing to experiment or take the risk but rely on factory supply.

To be fair, no spares are made for the T3 hub either, so it's a bit of a dead end. I managed to get a NOS spare axle key and the large bearing cages from Das Zweirad via someone in the Netherlands (they won't ship to the UK because of Brexshit), at vast expense, so mine will run for a good many years yet.

 

[yoho oy]

I would have insisted on the box. They are valuable as a Brompton doesn't fit in a normal bike box (unless fully unfolded and the bars turned, which is a faff for any potential buyer to reposition). The shop may be flogging it on eBay for £50.

Gee, it is just a cardboard box!!! Well it is too late now. I think the reason was that perhaps it was not my order number on a box which would mean that the store was cheeky and sold my bike to someone else (it was standard bike in common color) and later got another one that I got. I really doubt their story that bike needs to be somehow specially assembled compared with home delivery in a box.

 

[yoho oy]

I know that and you know that, but would you trust J. Random Ebayer to do it without leaving feedback on how you sold him a lethal bike?

I will try to keep my brommie as long as I can rather than to sell it after using it for a few months. This was the reason I went with brommie and foldable rather than some other and perhaps cheaper bike.

 

[yoho oy]

Brooks C17 saddle is a nightmare. Very stiff and actually probably a tad too narrow for my body type and taste. It is also somehow relatively slippery and I find myself slipping out of it. Now I have sore bum every time I take my bike for a bit longer ride. I don't understand who could pay full retail price in case the bike did not came with one. On a good note - as per product it seems it is made to last and could serve a lifetime on a bike. I guess everyone has a bit different body type and comfort requirements...

After having a bike for a longer time I came with a few shortcomings of it. Nothing major, just some nags. The first is Brooks saddle. Second - steering is sensitive and twitchy, bike feels way underweighted on front. Probably putting bag with some weight on front block would solve this issue. Also riding the bike for a while and more often would make me adjust to it. In general bike just rolls on its own on most terrain and most of the time I have to apply brakes rather than pedal it. Before I bought the bike I had an impression that due to smaller wheel size people have to pedal more on Brompton compared with normal size bike. It is not the case. It seems that bike is surprisingly quite fast and actually on some downhills I felt that it is way too fast for such small bike and my riding skill level. Another good thing is that going uphill is not that challenging compared with what I had in mind before I bought a bike and rode it for the first time. I haven't tried some extreme mountain hills, but relatively steep hills can be done without ever lifting a bum from a saddle. I have to stress that I am neither very fit nor spandex wearing bike enthusiast. In fact it was a while ago I rode a bike on regular basis. The model that I have is 6 speed, so might be it helps somehow...

But back to shortcomings... I think the bell is really rubbish. In fact a few times I was saved by relatively loud gear hub noise rather than a bell. I definitely will be adding a second after market bell. Also 100 psi are quite difficult to achieve with most pumps. I don't think I will be ever able to do it with included one, also the floor foot pump that I have is having a hard time too.

 

[CEBEP]

The model that I have is 6 speed, so might be it helps somehow...

But back to shortcomings... I think the bell is really rubbish. In fact a few times I was saved by relatively loud gear hub noise rather than a bell. I definitely will be adding a second after market bell. Also 100 psi are quite difficult to achieve with most pumps. I don't think I will be ever able to do it with included one, also the floor foot pump that I have is having a hard time too.

6 speeds does help, also 44T crank (smallest of 3 Brompton cranks) will help if you don't have it already. Awsome setup for Istanbul where no road is really flat.

Agree about bell and this is something I decided to invest in considering what I paid for this bike. Have just installed SpurCycle black bell. Sounds much louder than new one and looks awesome to my taste. Original can be removed if you wish. Here are few snaps with new one installed and original one removed.

 

[berlinonaut]

On a good note - as per product it seems it is made to last and could serve a lifetime on a bike. I guess everyone has a bit different body type and comfort requirements...

Saddles are a lot to individual taste. A lot of people like it. For my taste the C17 is ok but it is not my first choice. It seems btw. not to last as long as traditional Brooks leather saddles (let alone a lifetime) - at least with early models of the C17 endurance was not it's strong side and some people who ride a massive lot managed to wear it unexpectedly quick.

Before I bought the bike I had an impression that due to smaller wheel size people have to pedal more on Brompton compared with normal size bike.

That's not an impression - it is a prejudice, caused by a misunderstanding of physics. Interestingly pretty common - but still wrong.

But back to shortcomings...(....) Also 100 psi are quite difficult to achieve with most pumps. I don't think I will be ever able to do it with included one, also the floor foot pump that I have is having a hard time too.

I do own four pumps. None of them has issues going way beyond 100 PSI with ease. So the issue is not with "most pumps" - not at all. 100 PSI is not a high pressure when you look i.e. at traditional racing bikes. In opposite: It is more than common and rather on the low side. The included one is a pump for keeping mobile on the road, not a proper pump for every day. So your complaint is a bit as if you complained that your new ferrari prefers premium petrol but you only have a two stroke mix in a canister, intended for your lawn mower. Barely the fault of Ferrari or a fault at all. Same with Brompton's 100 PSI tyres. Buy a proper pump and you are set. The yellow Joe Blow Sport is a good but still very economic choice.

 

[rogerzilla]

The new bell is hopeless. The old 6-speed had a fairly good bell. Agree with berlinonaut's pump recommendation. I've had a Joe Blow Sport for years, and recently overhauled it (parts are available). I had an SKS Renkompressor too, but the heads were useless and the gauge fell apart.

 

[berlinonaut]

I had an SKS Renkompressor too, but the heads were useless and the gauge fell apart.

I have one, too. I like the Rennkompressor for it's style and heritage but cannot ignore to recognize that for one, when the Rennkompressor was invented, people were shorter than today (it is just a couple of cms too small for me to be comfy and requests a position which for me is perfect to hurt my back) and second, while it is more or less undistructable some things are more comfy on more modern pumps (though possibly not as long lasting): The Rennkompressor tends to fall over, the gauge is a bit small to read for the elderly cyclist, the wooden grip comes loose more or less regularly - tiny things like that. It is a bit the Land Rover of pumps. Regarding the heads: SKS offers three different ones to choose from and the most classic one seems to be the one that barely fails while the newer variants are not as robust. In principle one can add a third party head as well. If you are super-snobbish you import this one from Japan: https://www.tracksupermarket.com/st...d-presta-adapter-replacement-seal-3-pack.html (I've until now successfully avoided to do so but am still tempted... ).

 

[12boy]

Going back to the box issue. I bought my Brompton from a store in Denver, about 300 miles from home and didn't think to get a box. Years passed and the shop went away, but I needed a rebuild on the rear hinge and a new seatpost liner. The best place to have this done was about 1200 miles away and I needed to ship it there to I built a box from a fullsized box the LBS ( who don't work on Bromptons) gave me and FedExed the bike for repairs. When they returned it it was in a proper Brompton box which I am keeping for when mailing becomes needed again.

 

[Kell]

It is amazing that the shops don’t allow you to have these boxes any more. But everything seems to be monetised these days.

I sold an old MTB a while back and bought a box from what turned out to be a retailer on eBay.

It used to be case that they would just give you the boxes.